International human rights organisations today warned that many prominent activists and politicians have been arrested in Iran in response to protests over the country's disputed presidential election.

Opponents of Mahmoud Ahmadinejad have clashed with police in the heart of Iran's capital, pelting them with rocks and setting fires in the worst unrest in Tehran in a decade.

Iran’s Supreme leader Ayatollah Ali Khamenei said today any Western attempt to punish Tehran ovr its nuclear programme would jeopardise energy shipments, an implied threat to try to close the Strait of Hormuz choke point, through which much of the world’s oil supplies must pass.

Iran today admitted publicly to buying nuclear equipment from an international black market, including dealers on the Indian subcontinent, in a bid to display greater transparency and ease concerns over its controversial nuclear programme.